Question

(The Rectangle class) Following the example of the Circle class in Section 9.2, design a class named Rectangle to represent a rectangle. The class contains: ■ Two double data fields named width and height that specify the width and height of the rectangle. The default values are 1 for both width and height. ■ A no-arg constructor that creates a default rectangle. ■ A constructor that creates a rectangle with the specified width and height. ■ A method named getArea() that returns the area of this rectangle. ■ A method named getPerimeter() that returns the perimeter. Draw the UML diagram for the class and then implement the class. Write a test program that creates two Rectangle objects—one with width 4 and height 40 and the other with width 3.5 and height 35.9. Display the width, height, area, and perimeter of each rectangle in this order

Answer 1

class Rectangle
{
double width,height;

Rectangle()
{
width=1.0;
height=1.0;
}

Rectangle(double w,double h)
{
width=w;
height=h;
}

double getArea()
{
double area;
area=width*height;
return area;
}

double getPerimeter()
{
double per;
per=2*width+2*height;
return per;
}

public String toString()
{
return "Width : "+width+"\n"+"Height : "+height+"\n";
}
}

class TestRect
{
public static void main(String args[])
{
System.out.println("\n\nRectangle 1 : ");
System.out.println("------------------------------------------------------------\n");
Rectangle r1=new Rectangle(4,40);
System.out.println(r1);
System.out.println("Area of Rectangle : "+r1.getArea());
System.out.println("Perimenter of Rectangle : "+r1.getPerimeter());

System.out.println("\n\nRectangle 2 :");
System.out.println("------------------------------------------------------------\n");
Rectangle r2=new Rectangle(3.5,35.9);
System.out.println(r2);
System.out.println("Area of Rectangle : "+r2.getArea());
System.out.println("Perimenter of Rectangle : "+r2.getPerimeter());
System.out.println("\n");
}
}